An improved practice for the production of coiled sheet metal strip material is described in U.S. Pat. Nos. 4,155,238, 4,170,691 and 4,173,313 granted May 22, 1979, Oct. 9, 1979 and Nov. 6, 1979, respectively, to John W. Rogers. According to this improved practice an elongated web of sheet metal is slit along parallel lines in a manner that produces parting lines containing intermittently spaced residuums of only partially sheared metal that bridge the parting line between adjacent strips and interconnect their facing edges. Thus, upon coiling of the slit product there results a wound construct containing a plurality of coiled strips integrally joined by frangible connections or tabs defined by the aforementioned partially sheared residuums of metal.
Detachment of individual strips from the construct can be effected by a breakaway device such as that described in U.S. patent application Ser. No. 898,001 to John W. Rogers filed Apr. 20, 1978 now U.S. Pat. No. 4,195,759, granted Apr. 1, 1980 in which all the interconnecting tabs in the parting line to be separated are fractured substantially simultaneously by the application of a shear force directly to the concerned strip coil. Separating coils in this manner requires great forces due to the requirement to break all the tabs substantially together. The magnitude of the forces that must be applied to the web material requires the use of heavy, expensive equipment. It furthermore places the material in danger of being damaged due to deformation of the coiled strip selected for removal or of the remaining construct.
The above problem is avoided, however, through the use of an alternate form of apparatus, such as that described in U.S. patent application Ser. No. 055,848 to John W. Rogers filed July 9, 1979 in which the tabs in each parting line to be severed are fractured sequentially by paying the concerned strip over a wedge-like body. Use of this apparatus significantly reduces the degree of force required to separate the strip; however, removal of the strip in coil form is precluded unless, of course, the payed out strip is subsequently rewound into a coil.
In U.S. patent application Ser. No. 129,964, filed Mar. 13, 1980 to William A. Box, there is described a method of and apparatus for fracturing the tabs that attach a coiled strip to a construct in a manner that retains the separated strip in a coil. According to the practice of this invention, however, before the separated coil can be payed out to a work station such as a stamping press or the like, it must be transferred to a strip uncoiler. To transfer the separated strip from the construct at the separation station to an uncoiler at the processing station, of course, requires an expenditure of time, effort and equipment that is costly to any production process.
This problem is addressed in U.S. patent application Ser. No. 972,552 to John W. Rogers, now U.S. Pat. No. 4,191,318 which discloses an integrated coil separating and pay-out apparatus that is capable of both detaching a strip coil from a construct and of enabling the strip material to be unwound for feeding to a processing station. The described apparatus, while being capable of performing its intended function, suffers from the drawback that excessive operating forces are required for severing a coil from the construct and in that an external motive force is required for uncoiling the separated strip material.
Accordingly, it is to an improved form of apparatus of the described type, therefore, that the present invention is directed.